A device may include: a highly doped n.sup.+ Si region; an intrinsic silicon multiplication region disposed on at least a portion of the n.sup.+ Si region, the intrinsic silicon multiplication having a thickness of about 90-110 nm; a highly doped p.sup.− Si charge region disposed on at least part of the intrinsic silicon multiplication region, the p.sup.− Si charge region having a thickness of about 40-60 nm; and a p.sup.+ Ge absorption region disposed on at least a portion of the p.sup.− Si charge region; wherein the p.sup.+ Ge absorption region is doped across its entire thickness. The thickness of the n.sup.+ Si region may be about 100 nm and the thickness of the p.sup.− Si charge region may be about 50 nm. The p.sup.+ Ge absorption region may confine the electric field to the multiplication region and the charge region to achieve a temperature stability of 4.2 mV/° C.

Systems and methods are provided for zero-added latency communication between nodes over an optical fabric. In various embodiments, a photonic interface system is provided that comprises a plurality of optical routing elements and optical signal sources. Each node within a cluster is assigned an intra-cluster wavelength and an inter-cluster wavelength. All the nodes in a cluster are directly connected and each node in a cluster is directly connected to one node in each of the plurality of clusters. When an optical signal from a different cluster is received at a node serving as the cluster interface, the photonics interface system allows all wavelength signals other than the node's assigned wavelength to pass through and couple those signals to an intra-cluster transmission signal. Zero latency is added in rerouting the data through an intermediate node.

Systems and methods are provided for zero-added latency communication between nodes over an optical fabric. In various embodiments, a photonic interface system is provided that comprises a plurality of optical routing elements and optical signal sources. Each node within a cluster is assigned an intra-cluster wavelength and an inter-cluster wavelength. All the nodes in a cluster are directly connected and each node in a cluster is directly connected to one node in each of the plurality of clusters. When an optical signal from a different cluster is received at a node serving as the cluster interface, the photonics interface system allows all wavelength signals other than the node's assigned wavelength to pass through and couple those signals to an intra-cluster transmission signal. Zero latency is added in rerouting the data through an intermediate node.

A method for transmitting data carrying optical information over an optical channel, comprising the steps of providing an optical transmitter consisting of a light source being a Mode-Locked Optical Frequency Comb (MLFC) for generating a frequency comb of multiple carriers, each of which being modulated by a baseband signal; an optical modulator for modulating each and all of the multiple carriers in a modulation bandwidth extending up to the modes' frequency spacing between the multiple carriers; performing all-optical encoding of the modulated carriers by manipulating the optical amplitude and/or phase and/or polarization of all optically modulated carriers; and transmitting, by the optical transmitter, the encoded modulated carriers to an optical receiver, over an optical channel

An optical module includes an interface electrically connected to an external device to receive a data signal to be transmitted, a signal processor configured to perform serialization and signal modulation on the received data signal, an optical transceiver configured to generate an optical transmission signal by receiving a direct current (DC) light source, in which a plurality of light sources having different wavelengths are multiplexed, from an optical power supply and performing optical modulation thereon through the serialized and modulated data signal, and an optical fiber connector configured to output the generated optical transmission signal to the external device and receive an optical reception signal from the external device.

A wireless optical transceiver, comprising: a light splitter for splitting light emitted from a light source into two lights; a data converter for dividing input data into a plurality of divided data in a symbol unit of a predetermined number of bits, and for converting values of a phase bit and a duty bit at a predetermined position in each of the divided data into a phase control signal and a blocking control signal; a modulator for polarization phase modulating two lights split according to the phase control signal, and for conveying or blocking two modulated polarized lights in response to the blocking control signal to modulate a pulse position; a polarized light combiner for generating a transmission optical signal by combining two polarized lights with a modulated polarization phase and a modulated pulse position; and a light amplifier for amplifying the transmission optical signal and transmitting it through a standby channel.

A wireless optical transceiver, comprising: a light splitter for splitting light emitted from a light source into two lights; a data converter for dividing input data into a plurality of divided data in a symbol unit of a predetermined number of bits, and for converting values of a phase bit and a duty bit at a predetermined position in each of the divided data into a phase control signal and a blocking control signal; a modulator for polarization phase modulating two lights split according to the phase control signal, and for conveying or blocking two modulated polarized lights in response to the blocking control signal to modulate a pulse position; a polarized light combiner for generating a transmission optical signal by combining two polarized lights with a modulated polarization phase and a modulated pulse position; and a light amplifier for amplifying the transmission optical signal and transmitting it through a standby channel.

An amplified optical link having a fault-protection capability that is based, at least in part, on the ability to selectively and independently power up and down different groups of optical amplifiers within the link. In an example embodiment, the optical link is implemented using an optical fiber cable having an electrical power line and arrays of optical amplifiers connected between successive optical fiber segments to form a plurality of disjoint groups of parallel optical paths between the ends of the optical fiber cable. The electrical power line is operable to selectively power, as a group, the optical amplifiers of at least some of the disjoint groups. In various embodiments, different optical paths can be implemented using different respective strands of a single-core optical fiber, different respective cores of a multi-core optical fiber, and/or different respective sets of spatial modes of a multimode optical fiber.

In some examples, high speed bidirectional OTDR-based testing may include transmitting data from a first end of a device under test (DUT) towards an optical time-domain reflectometer (OTDR) that is operatively connected to a second opposite end of the DUT. Further data that is transmitted by the OTDR may be received from the second opposite end of the DUT towards the first end of the DUT. Based on an amplitude of the further data, a direction of receiving of the further data may be adjusted towards a first receiver or towards a second receiver.

In some examples, high speed bidirectional OTDR-based testing may include transmitting data from a first end of a device under test (DUT) towards an optical time-domain reflectometer (OTDR) that is operatively connected to a second opposite end of the DUT. Further data that is transmitted by the OTDR may be received from the second opposite end of the DUT towards the first end of the DUT. Based on an amplitude of the further data, a direction of receiving of the further data may be adjusted towards a first receiver or towards a second receiver.